1. Field of the Invention
The present invention relates to the field of actuation levers. More particularly, it relates to a lever that rotates about a first axis that is central to the lever while the lever pivots about a second axis of rotation orthogonal to the first axis.
2. Description of the Prior Art
A lever connected to a pivot hinge is a well-known device for actuating countless mechanisms. A typical example is a lever to actuate a brake or clutch on a bicycle or motorcycle. The operator, to release the clutch or apply the brakes, pulls a lever that is pivotably mounted on the handlebar toward the handlebar. A brake or clutch cable is attached to the lever and pulling on the lever pulls on the cable.
A major disadvantage of the conventional pivot-hinge lever is that it requires a fair amount of force to actuate the mechanism. This is particularly disadvantageous when the pivot-hinge lever is mounted such, that the operator must grasp it with his or her fingertips, as is conventionally the case with brake or clutch levers on bicylces or motorcycles. The levers are spring-biased to return to a resting position. To operate the lever, the operator keeps the palm of his or her hand on the handlebar and reaches with the fingertips to grasp the lever and pull it toward the handlebar. In doing so, the operator has to expend significant effort to maintain control of the lever and to prevent it from springing back to its biased position. Unfortunately, the fingertips do not have as much strength as the base end of the fingers have closer to the palm of the hand. The disadvantage is exacerbated by the fact that the lever may have to be held in the squeezed position for a period of time that is long enough to cause fatigue and pain in the operator's hand, or worse, that causes the operator to inadvertently let go of the lever and lose control over the brake or clutch function.
Another example of such a pivot-hinge lever is found in the grips of tools, such as a pair of pliers or shears, or a hand exercise device. Pulling one handle toward the other or squeezing both handles together forces the operating ends of the tool together. With some tools, the handles are far apart and the operator is using his or her fingertips to grasp one of the handles. The same difficulties as described above apply to the operation of such tools. The operator is using fingertips to exert force on a lever and to maintain control over it, resulting in strain and fatigue of the fingers after only a short time of use. With the hand exercise device, the purpose is to strengthen the hand muscles, not necessarily those of the outer fingertips. With some conventional hand exercise devices, the fingertips may be required to exert undue force and strength to pull one handle toward the other to the point where the handles are close enough together that the major muscles of the hand are then used to squeeze the handles together. This is a disadvantage, as repetitive exercises with the hand device cause undue strain and fatigue on the fingertips.
Yet another example of such a pivot-hinge lever is a gun trigger. It is highly desirable to pull back on the trigger with force evenly applied in the direction of the trigger action, without applying lateral forces to the trigger, as they may may skew the aim. The fingertip up to the first finger joint is typically used to appy force to the trigger. The conventional trigger does not accommodate for any lateral forces applied by the trigger finger and it requires a great deal of training to fire a gun with the desired control and aim.
What is needed therefore, is an actuation lever that eases the strain of holding a mechanism in a particular state of actuation. What is further needed is such an actuation lever that moves the point of force exertion away from the tips of the fingers in toward the base of the fingers. What is yet further needed is such an actuation lever that is simple and inexpensive to manufacture.